Implementation of Hospital Policy for Healthcare Workers and Patients Exposed to Varicella-Zoster Virus

AbstractWe surveyed healthcare workers to determine factors that may influence acceptance of varicella-zoster virus vaccine. Of 2,801 workers tested, 90 were susceptible to varicella; of workers offered vaccination, 68% accepted. Workers providing direct patient care were 3.7-fold more likely than other workers to accept VZV vaccination (P=.04).

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Screening Healthcare Workers for Varicella-Zoster Virus: Can We Trust the History?

Infection Control and Hospital Epidemiology ◽

10.1086/502445 ◽

2004 ◽

Vol 25 (7) ◽

pp. 595-598 ◽

Cited By ~ 24

Author(s):

Maha Almuneef ◽

Ziad A. Memish ◽

Mostafa F. Abbas ◽

Hanan H. Balkhy

Keyword(s):

Varicella Zoster Virus ◽

Predictive Value ◽

Healthcare Workers ◽

Middle Eastern ◽

Enzyme Linked Immunosorbent Assay ◽

New Employees ◽

Varicella Zoster ◽

History Of ◽

Serologic Screening ◽

New Recruits

AbstractObjective:To determine the relationship between immunity and a history of chickenpox based on a self-administered questionnaire.Methods:We investigated immunity to varicella-zoster virus in a cohort of newly recruited employees with different job categories and different nationalities using enzyme-linked immunosorbent assay IgG.Results:There were 1,058 new recruits. Of these, 890 (84%) were immune and 168 (16%) were susceptible. The susceptibility rate was 23% (n = 77) for Asian, 15% (n = 14) for South African, 13% (n = 66) for Middle Eastern, and 9% (n = 11) for Western employees. Physicians were more likely to be immune (93%) than were nurses (85%), medical technicians (75%), or administrative clerks (84%). Seropositivity was not affected by age or gender. The positive predictive value of a history of chickenpox for the seropositivity was 89% (511 of 574); the negative predictive value was 22% (105 of 484). History of chickenpox had a sensitivity of 57% (511 of 890) and a specificity of 63% (105 of 168).Conclusions:The varicella-zoster virus seroprevalence among new employees was low, posing an important risk to existing employees and patients. Positive or negative history of chickenpox was an unreliable indicator of susceptibility among healthcare workers of different nationalities. Serologic screening of all employees and vaccination of those susceptible was recommended.

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Varicella zoster virus infection among healthcare workers in Taiwan: seroprevalence and predictive value of history of varicella infection

Journal of Hospital Infection ◽

10.1016/j.jhin.2011.11.011 ◽

2012 ◽

Vol 80 (2) ◽

pp. 162-167 ◽

Cited By ~ 20

Author(s):

M.-F. Wu ◽

Y.-W. Yang ◽

W.-Y. Lin ◽

C.-Y. Chang ◽

M.-S. Soon ◽

...

Keyword(s):

Virus Infection ◽

Varicella Zoster Virus ◽

Predictive Value ◽

Healthcare Workers ◽

Varicella Zoster Virus Infection ◽

Varicella Infection ◽

Varicella Zoster ◽

History Of

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Persistence of Immunity to Varicella-Zoster Virus After Vaccination of Healthcare Workers

Infection Control and Hospital Epidemiology ◽

10.1086/501900 ◽

2001 ◽

Vol 22 (5) ◽

pp. 279-283 ◽

Cited By ~ 51

Author(s):

Lisa Saiman ◽

Philip LaRussa ◽

Sharon P. Steinberg ◽

Juyan Zhou ◽

Keren Baron ◽

...

Keyword(s):

Varicella Zoster Virus ◽

Healthcare Workers ◽

Fluorescent Antibody ◽

Latex Agglutination ◽

Serological Tests ◽

Specific Antibodies ◽

Varicella Zoster ◽

Vaccine Trials ◽

Serious Disease ◽

Study Participants

AbstractObjective:Varicella-zoster virus (VZV) vaccine is recommended to protect susceptible healthcare workers (HCWs) from serious disease and to prevent nosocomial spread of VZV. We evaluated clinical outcomes and serological responses in HCWs after immunization with live attenuated VZV vaccine.Design:Vaccinees were immunized from 1979 to 1998 during VZV vaccine trials, as well as after licensure, and followed prospectively for 1 month to 20.6 (mean 4.6) years after vaccination. Sera were tested by fluorescent antibody to membrane antigen (FAMA), latex agglutination (LA), and enzyme-linked immunoassay (EIA) to detect VZV-specific antibodies.Study Participants:The median age of the 120 HCWs was 26 years; 51 (42%) were males.Interventions:Ninety eight (82%) of these study subjects received vaccine prepared by Merck and 22 (18%) by SmithKline Beecham; 25, 81, and 14 vaccinees received one dose, two doses, and three doses, respectively.Results:The crude attack rate was 10%; 12 of 120 HCWs developed chickenpox 6 months to 8.4 years after vaccination. The attack rates following household and hospital exposures were 18% (4/22) and 8% (6/72), respectively. All resulting illness was mild to moderate (mean 40 vesicles). Seroconversion after vaccination was documented by FAMA in 96% of HCWs, although 31% lost detectable antibodies. Compared with FAMA, LA and EIA were 82% and 74% sensitive and 94% and 89% specific, respectively.Conclusions:The VZV vaccine effectively protected HCWs from varicella, particularly from serious disease. Currently available serological tests are not optimal, and improved assays are needed.

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Long -Term Persistence of Antibodies Against Varicella in Fully Immunized Healthcare Workers: An Italian Retrospective Cohort Study

10.21203/rs.3.rs-142042/v1 ◽

2021 ◽

Author(s):

Francesco Bianchi ◽

Silvio Tafuri ◽

Angela Larocca ◽

Cinzia Germinario ◽

Pasquale Stefanizzi

Keyword(s):

Varicella Zoster Virus ◽

Healthcare Workers ◽

Varicella Vaccine ◽

Serious Adverse Events ◽

Biological Risk ◽

Varicella Zoster ◽

Vaccine Booster ◽

History Of ◽

Study Population

Abstract Background. Chickenpox is a highly contagious disease caused by the varicella zoster virus (VZV), and in infants, adolescents, adults, pregnant women, and the immunocompromised it can be serious. The best way to prevent chickenpox is immunization with the varicella vaccine. Protective levels of antibodies induced by the varicella vaccine decline over time, but there is currently no formal recommendation for testing anti-varicella zoster virus (VZV) IgG levels in immunized healthcare workers (HCWs). Methods. The aims of this study were to evaluate the seroprevalence of circulating anti-VZV IgG in a sample a sample of students and residents of the medical school of the University of Bari, the long-term immunogenicity of the varicella vaccine, and the effectiveness of a strategy consisting of a third vaccine booster dose. The study population was screened as part of a biological risk assessment conducted between April 2014 and October 2020. A strategy for the management of non-responders was also examined. Results. The 182 students and residents included in the study had a documented history of immunization (two doses of varicella vaccine). The absence of anti-VZV IgG was determined in 34% (62/182; 95%CI=27.2–41.4%), with serosusceptibility more common among males than females (p<0.05). After a third varicella dose, seroconversion was achieved in 100% of this previously seronegative group. No serious adverse events were recorded. Conclusions. One-third of the study population immunized against VZV lacked a protective antibody titer, but a third dose of vaccine restored protection. Since it is highly unlikely that VZV will be eliminated in the immediate future, the loss of immunity in a substantial portion of the population implies a risk of varicella outbreaks in the coming years. Screening for varicella immunity in routine assessments of the biological risk of medical students and HCWs may help to prevent nosocomial VZV infections.

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Long -term persistence of antibodies against varicella in fully immunized healthcare workers: an Italian retrospective cohort study

BMC Infectious Diseases ◽

10.1186/s12879-021-06180-x ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Francesco Paolo Bianchi ◽

Silvio Tafuri ◽

Angela Maria Vittoria Larocca ◽

Cinzia Annatea Germinario ◽

Pasquale Stefanizzi

Keyword(s):

Varicella Zoster Virus ◽

Healthcare Workers ◽

Varicella Vaccine ◽

Serious Adverse Events ◽

Biological Risk ◽

Varicella Zoster ◽

Vaccine Booster ◽

History Of ◽

Study Population

Abstract Background Chickenpox is a highly contagious disease caused by the varicella zoster virus (VZV), and in infants, adolescents, adults, pregnant women, and the immunocompromised it can be serious. The best way to prevent chickenpox is immunization with the varicella vaccine. Protective levels of antibodies induced by the varicella vaccine decline over time, but there is currently no formal recommendation for testing anti-varicella zoster virus (VZV) IgG levels in immunized healthcare workers (HCWs). Methods The aims of this study were to evaluate the seroprevalence of circulating anti-VZV IgG in a sample a sample of students and residents of the medical school of the University of Bari, the long-term immunogenicity of the varicella vaccine, and the effectiveness of a strategy consisting of a third vaccine booster dose. The study population was screened as part of a biological risk assessment conducted between April 2014 and October 2020. A strategy for the management of non-responders was also examined. Results The 182 students and residents included in the study had a documented history of immunization (two doses of varicella vaccine). The absence of anti-VZV IgG was determined in 34% (62/182; 95%CI = 27.2–41.4%), with serosusceptibility more common among males than females (p < 0.05). After a third varicella dose, seroconversion was achieved in 100% of this previously seronegative group. No serious adverse events were recorded. Conclusions One-third of the study population immunized against VZV lacked a protective antibody titer, but a third dose of vaccine restored protection. Since it is highly unlikely that VZV will be eliminated in the immediate future, the loss of immunity in a substantial portion of the population implies a risk of varicella outbreaks in the coming years. Screening for varicella immunity in routine assessments of the biological risk of medical students and HCWs may help to prevent nosocomial VZV infections.

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A Cluster of Primary Varicella Cases Among Healthcare Workers With False-Positive Varicella Zoster Virus Titers

Infection Control and Hospital Epidemiology ◽

10.1086/502187 ◽

2003 ◽

Vol 24 (3) ◽

pp. 202-206 ◽

Cited By ~ 26

Author(s):

Amy Behrman ◽

D. Scott Schmid ◽

Anne Crivaro ◽

Barbara Watson

Keyword(s):

Varicella Zoster Virus ◽

False Positive ◽

Healthcare Workers ◽

Screening Program ◽

Varicella Vaccine ◽

Varicella Zoster ◽

Control And Prevention ◽

Serologic Screening ◽

Positive Results

AbstractBackground:Five cases of primary varicella zoster virus (VZV) were diagnosed among hospital healthcare workers (HCWs). All had complied with a pre-employment VZV screening program and had been considered immune.Objectives:To summarize the investigation of VZV among un-immunized HCWs and to provide recommendations for avoiding false-positive serologic tests.Design:Risk of transmission of VZV to susceptible HCWs is minimized through serologic screening. Varicella vaccine is recommended for susceptible HCWs. A commercially available latex bead agglutination assay (LA) is widely used because it is rapid and easy to perform. LA was compared with the whole-cell varicella ELISA standardized in the Centers for Disease Control and Prevention (CDC) National Herpes Laboratory.Setting/Population:Large inner-city, tertiarycare hospital with a diverse employee population.Results:In a year, 5 HCWs presented with laboratory-confirmed primary varicella infection. Four had VZV exposures 2 weeks prior to presentation. All had documented positive VZV titers by LA performed at hire. None were offered VZV vaccination. The original LAs were judged false-positives.Intervention/Follow-Up Investigation:Fifty-three consecutive VZV LA samples from the hospital laboratory were retested at the CDC. Forty-four samples concurred. Of the remaining 9, 4 were positive by hospital LA but negative by CDC IgG ELISA. Four were equivocal by hospital LA but negative by CDC IgG ELISA and LA. One was positive by hospital LA but negative by LA and equivocal by ELISA at the CDC.Conclusion:LA may be prone to false-positive results and inappropriate for screening hospital HCWs.

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